House electric



' 164 ,7 7 Sept. 27,1927. K. ROTTGARDT 3 8 CONTROL UNIT FOR VARIABLEINSTRUMENTS Filed Au'2;.;29, 1921 fl 5 a;

I Z /7 J9 Z0 Z/ w w & T T N '/5 INVENTOIT WWW A TTORNE Y5 Patented Sept.27, 1927.

' UNITED STATES PATENT OFFICE.

KARL ROTTGARDT, OF DAHLEM, NEAR BERLIN, GERMANY, ASSIGNOR T0 WESTING-HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

Application filed August 29, 1921, Serial No. 496,433, and in GermanyNovember 2, 1918.

The invention refers to adjustment clevices for apparatus such ascondensers and variometers for radiotelegraphy in which it is necessaryto make provision not only for approximate adjustments of movablemembers, but also for accurate adjustments of such members. According tothe invention such adjustment device is designed in such a manner as tobe handy, convenient and compact in spiteof the fact of its affordingthe possibility of a double range of adjustments. The invention attainsthis purpose by making provision for two separate handles arranged as arule one inside the other, and intended respectively for the accurateand the approximate adjustment, and for a transmission gearing makingpossible the accurate adjustment, which transmission gearing is locatedinside the handle for the approximate adjustment. There is obtained inthis manner an extremely compact design of the two handles, which can bearranged. on the same axis, the large handle acting as bearing for theaxis or spindle of the small handle. Such arrangement makes it possibleto operate conveniently both handles in succession with a single hand.The contemplated design makes it possible to consolidate the entireadjustment contrivance into a compact unit which can be convenientlymounted on the apparatus in question as a mere adjunct and can be easilytaken down or removed wherever it is'desired to do so. The transmissiongearing enclosed in the large handle may-be conveniently provided with asliding coupling whereby the driven spindle is coupled with the smallhandle only in case an accurate adjustment is desired, but which remaininoperative when the large handle is used. It is also advisable to giveto the transmission the form of a friction gearing in order to do awayfor instance with the clearance which cannot be avoided in case oftoothed gears. The simplification of the entire arrangement is promotedby utilizing the large handle as a member of the transmission gearinserted in front of the small handle, for instance by having a frictionor toothed wheel of this gearing mesh with a likewise designed member onthe inner wall of the large handle.

A clearer understanding of this invention may be had from the followingdescription of the preferred embodiments which are illustrated in theaccompanying drawing. In this drawing.

Fig. 1 illustrates a control unit comprising two handles which areoperatively conneeted by means of toothed gears;

Fig. 2 illustrates a similar control unit in which the two handles areconnected by means of frictional gears. I Referring now to 1, a handle 1havlng an interior recessed portion is securely attached to a shaft 5,which is journaled in an insulating member 7, and is releasablyconnected to the shaft of a variable instrument 4, which may be acondenser or a variometer for use in wireless receiving or transmittingdevices. On an extended portion of the shaft 5 a smaller handle 3 isrevolubly mounted so that a portion of the smaller handle extends withinthe handle 1. A pinion gear 8 is securely attached to the shaft ofhandle 3, and meshes with a larger pinion gear 9, which is carried on arevoluble shaft 10. This shaft 10 may be mounted on the insulating block7, a portion of the handle 1 being cut away to allow free movementthereof. A pinion 11, which is revolubly mounted on the shaft 5, engageswith a second pinion 12, which is preferably cut on the shaft 10. Aspring thrust 6, which is securely attached to the shaft 5 and bearsagainst the pinion 11, is adapted to transmit motion from the pinion 11to the shaft 5 and thus to the variable device 4.. The use of africtional spring engagement between the pinion 11 and the shaft 5 ishighly advantageous, as when adjustments are made by means of the handle3, due to the small speeds and forces involved, the friction will beeflective in connecting the pinion 11 with the shaft 5, but whenadjustment is made through handle 1, the relative speed of handie 3 isso much greater that pinion 11 will shp with respect to the springthrust 6 so that the handle 3 will not turn.

Adjustment of the variable device 4 by means of this arrangement may bemade as follows:

By turning the handle 1 the variable device 4 is adjusted approximately.The small handle 3 is then turned, and motion is transmitted through thegear train 8, 9, 12, l1 and the thrust spring 6 to the shaft 5. It willbe seen that because of the relative sizes of the gears, for a givenangle of rotation of the handle 3, the handle 1 and consequently thevariable device 4:, w ll move through a relatively smaller angle, andextremely accurate adjustment of the variable devic at may be made.

In Fig. 2 a modified form of control unit is shown in which frictionalgearing is employed instead of toothed wheel gearing, as it is foundthat accurate adjustment is impossible with toothed wheel gearingbecause of the back lash in the gearing which occurs after the gearshave become slightly worn and is unavoidable. In this embodiment thehandle 1, to which is securely attached the shaft 5, is journaled in ayoke 18, which is adapted to be attached to a panel 15 or otherconvenient support. The handle 3 is journaled in a portion of the handle1 preferably concentrically with the shaft 5', and extends through thewall of the handle into the hollow interior. A semicircular slot is cutin the bottom portion of the hanoie 1' through which extends the support1 1, in a portion of which is jou naled a shaft 16, on one end of whichis freely mounted a wheel 17, and on the other end of which issecurelyattached a smaller wheel 18. A plate 19 is securely attached to theshaft 16 and is frictionally engaged with the wheel 17 by means of aspring (5, which may take the form of a spring washer. The transmissionmembers carried by the shaft 16 are positioned so that the free wheel1'? engages with the disc 23 on the end of the shaft of the handle 3'and the pinion 18 engages with the annular portion 20 of the handle 1.In order to maintain the contact between the wheel 17 and the disc 23and the pinion 1S and the annular portion 20, the block 21, in which theshaft 16 is journaled, is supported by means of springs 22, which bearagainstthe support 1 1 and tend to force the block 21 upwards so thatthe parts 17 and 18 are held in good frictional engagement with themembers 19 and 2O respectii' ely.

The mode of using the handle illustrated in Fig. 2 is substantially thesame as previously outlined, but the various parts, of course, functiondifferently. An approximate adjustment ismdo by means of the handle 1,and the final or accurate adjustment is made by means of the handle 3'.

The movement of the handle 3 is transmitted to the free wheel 17, whichengages the plate 19 by means of the thrust-sprin 6. Motion is thereforetransmitted through the shaft 16 and the pinion 20 to the handle 1.Because of the reduction in goarin flm movement of handle 1 isrelatively less than that of handle 3, which enables the aceu= rateadjustment to be made. It will be seen that when the handle 1 isgrasped, the hand f the operator will enclose the n1 henthe '3, and tendto prevent its toenai -n a greater speed than that of handle 1'. Thenecessary slip occurs preferably between the members 17 and 19, whichare connected one with another only by means of the thrust spring 6.

It is to be understood that the foregoing description of preferredembodiments is not to at all limit the spirit and scope of thisinvention, as various modifications will at once be apparent to thoseskilled in the art.

I claim 1. A control unit for adjustable instruments comprising ahandle, means for mounting said handle on an instrument, a second handlejournaled concentrically with the first-mentioned handle, and reductiongearing between said handles for transmit-- ting motion by means ofeither handle, said gearing including frictional connections, wherebythe first-inentionecl handle may be moved in either direction withoutcausing motion of the other handle. I

2. A control unit for adjustable instruments comprising a handle, meansfor mounting said handle on an instrument, a second handle journaled insaid first-mentioned handle and concentrically therewith, and reductiongearing between said handles for traiisi'nitting motion by means ofeither handle, said gearing including a device yieldable in eachdirection, whereby either direct or reduced motions may be trans mittedin either direction.

3. A control "unit for adjustable instru ments comprising a handle,means for mounting said handle on an instrument, a second handlejournaled in said first-mentioned handle and concentrically therewith,and reduction gearing between said handles for transmittiiw motion bymeans of either of said handles, said gearing including a frictionclutch whereby one handle may be rotated without rotating the other.

1-. A control unit for adjustable instruments comprising a handle havinga depending annular flange forming ii" cavitv therein, a second handlejournaled conceiitrlcally with the first-mentioned handle and extendingtherethrough into the cavity thereof, and gearing contained within thecavity of said first-mentioned handle for transmitting motion by means;or either handle.

A control unit for adjustable instruments comprising a handle having ade' pendin annular flange formin cavity therein, a s cond handlejournaled in said first-mentioned handle and concentrically therewithextending therethrough into the cavity thereof, and gearing containedwithin the hollow ca i of said first-mentioned ha dle and connected withboth handles eby motion may be transmitted by means of either handle.

8. A control unit for adjustable instrumerits comprising a handle havinga depending annular flange forming a cavity therein, a second handlejournaled in said first-mentioned handle and concentrically therewithextending therethrough into the cavity thereof, and gearing containedwithin the hollow cavity of said first-mentioned handle and connectedwith both handles whereby motion may be transmitted by means of eitherhandle, said gearing including a friction clutch whereby one handle maybe rotated without rotating the other.

7. A control unit for adjustable instruments comprising a handle havinga depending annular flange forming a cavity therein, a shaft attached tosaid handle, said shaft being journaled in a mounting block, a secondhandle journaled in said first mentioned handle and extendingtherethrough, reduction gearing mounted on said block and extendingwithin the cavity in said first-mentioned handle to transmit mo tionfrom one handle to the other and in eluding a gear frictionally engagedwith said second handle, a gear frictionally engaged with saidfirst-mentioned handle, and a slidable friction clutch interposedbetween said gears, said clutch permit-ting one handle to be rotatedwithout rotation of the other of said handles.

8. A control device for variable electrical apparatus comprising a mainknob adapted to be connected to a shaft for directly rotating saidshaft, speed reducing mechanism enclosed by said main knob, and anauxiliary knob for operating said speed reducing mechanism.

9. In a control device a shaft, a handle, a plate connecting said handleto said shaft, a second handle and a slow motion device connecting saidsecond handle to said shaft, said plate having an opening foraccommodating movement thereof relative to said slow-motion device.

10. In an adjustable device, a member to be moved, a handle directlyconnected to said member, a second handle and a slowmotion deviceconnecting said second handle to said member, said slow-motion deviceincluding parts having slip engagement, whereby the member may be movedin either direction by either handle.

11. The combination of a radio apparatus tuning shaft, indicating meansrigid with said shaft, a handle for operating said shaft, andinstrumentalities having a plurality of longitudinal and parallel andfixed axes of rotation whereby said shaft is rofated in the samedirection but at a slower speed by the rotation of said handle, saidinstrumentalities comprising a smaller shaft whereby said handle ismovably supported and which is integral with the outer end portion ofsaid tuning shaft to communicate the motion of said handle thereto,whereby removal of the handle from said smaller shaft is necessary inorder to disconnect the handle from said tuning shaft.

12. The combination of a radio apparatus tuning shaft, indicating meansrigid with said shaft, a rotary handle supported entirely by and adaptedfor operating said shaft, extending outwardly beyond the plane ofmovement of said indicating means, so that the indicating means areimmediately behind the handle, instrumentalities having a plurality oflongitudinal and parallel and fixed axes of rotation whereby said shaftis rotated in the same direction but at a slower speed by the rotationof said handle, so that said indicating means and handle always turn inthe same direction, but with the indicating means turning more slowlythan the handle. said instrumentalities comprising an engaging memberrigid with said handle, and means to engage said engaging member toimpart slow movement to said shaft and indicating means, said shaftbeing necessary to maintain said engaging member in operative position.

In testimony whereof I affix my signature.

DR. KARL ROTTGARDT.

